SEAMARC-1 



A commercially available deep-towed geophysical instrument package. 



Sedimentary process 



Relief-forming process which involves the transportation of 

 suspended material. 



Sine function 



The function y = sin(x)/x. 



Sinusoid 



A function having the form of a sine or cosine function, but with a 

 variable phase value. 



Spatial frequency 



The inverse of wavelength. 



Spectral intercept 



The intersection of an amplitude spectrum with the amplitude axis. 

 This term is specific to this report. 



Spectral slope 



The slope of an amplitude spectrum which has been plotted on log- 

 log axes. This value becomes the exponent of spatial frequency 

 following transformation to linear-linear space. This term is spe- 

 cific to this report. 



Spreading center 



A region of the sea floor where recent crustal material is being 

 formed . 



Stationarity 



Although rigorously defined in statistical theory, used in this 

 report to imply relative constancy of a particular statistical 

 parameter as a function of position; statistically homogeneous. 



Stereo-pair bottom photography 



A photogrammetric technique which allows the measurement of micro- 

 relief on the sea floor by analyzing photographic images of a sur- 

 face from offset viewpoints. 



Stochastic model 



A numerical model in which the mathematical parameters describe the 

 process under study in terms of its random variability. 



Strike 



The bearing of the long axis of a linear trend. 



Tectonic process 



Relief -forming process which involves the deformation of the 

 earth's crust. 



White noise 



A random series whose amplitude spectrum is constant with fre- 

 quency. 



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